DE2610149A1 - Spatial contour measurement head for large measurement paths - has variable gain and large sensor inclination angles in 3 coordinates from ball bearing mounting - Google Patents

Abstract

A sensing head for measurement of spatial contours has the contact part connected to guide elements and is designed for very large measurement paths and operation at large sensor deflections. The sensor gain is variable. The moving part of the sensor, which activates the signal generator, can move in all directions in the x-y plane and simultaneously in the z direction perpendicular to the x-y plane. The three-coordinate movement is achieve using a ball bearing with a movable mounting. The profile of the moving sensor part is so formed as to give max. measurement sensitivity with sufficient linearity.

Description

Probe head for measurement

spatial contours.

The invention relates to a probe head for measuring spatial contours, in which the part of the probe touching the measuring contour is movable with guide elements connected is.

In such measuring machines, the contour to be measured is touched a probe clamped in the measuring machine and the coordinates measured are shown. There should be no accelerations at the moment of the measurement occur in the moving parts of the measuring machine.

With the known knot heads, for example, the displacement of the movable Part via lever, spring or translational guide systems in two or three Components are laid down, each of which is indicated by a transmitter independently of one another will. The disadvantage of these systems is their high design and manufacturing costs and in certain applications their exclusive movement in the straight lines of the three coordinates. Another probe head design is the actual probe element as a whole, movably mounted in any direction, e.g. via membrane springs The short measuring path and the only additional construction effort have an effect here achievable three-way, which, for example, also allows a larger crossing of the measuring contour.

The invention is based on the object of developing a button keln, the structurally simple structure can be moved in any spatial direction is and position, speed as well as direction of the movement via position and angle sensors into an electrical signal 0 According to the invention, this task is achieved by that the signal transmitter controlling part in each direction of the x-y plane and at the same time movable in the z-axis lying perpendicular to the x-y plane is and while on slideways with a predetermined course according to certain requirements electrical signal transmitter acts.

The principle of two exemplary embodiments of the invention is shown in FIG. 1 and 2 outlined. The translational storage for movement in direction consists from the stationary cylinder (1), in or above which the cylinder (2) is free of play and is resiliently (3). The all-round movement in the x-y plane is about the ball or tip bearing (4) of the probe element, consisting of the contour element (5) and the stylus (6) in which the guide cylinder (2) is reached. Controlling the Displacement encoder (7) is effected via the conical surface of the contour element (5). The probe balls (8) the displacement transducers (7) are arranged in one plane. Position transducer and guide cylinder (1) are firmly connected to the button housing, not shown here, which defined is clamped in the quill of a coordinate measuring machine. Likewise are the spring elements that hold the probe element (5,6) in the central position, and any damping elements not shown.

In the embodiment example in Fig. 2 is above the guide cylinder (2) a third cylinder (9) is arranged so that it can be displaced without play in the z direction. If measurements are only to be made in the z-direction, this cylinder (9) pushed onto the contour element (5), eo that it prevents pivoting movements locked.

The axial movement of the cylinder (9) and the pressing against the contour element (5) can be caused by an electric magnet. 0 E.g., the cylinder (9) are held in the rest position by means of a spring. Act when the magnet is excited then forces between the cylinders (2) and (9), the latter against the spring forces press on the contour element (5).

The advantages achieved with the invention are in particular: that the probe is built for very large measuring and free paths connected to it can be. It is thus possible to measure values over a large deflection range of the probe to detect and to allow a free path beyond the measuring range beyond the still There is no need to fear damage to the button. The translation can also be used the movement of the movable button element to which the signal transmitter can be varied widely.

What is essential is the relatively low cost of manufacturing due to the simple Storage as well as the possibility of using commercially available signal generators, e.g. inductive Weggeber to be able to use.

Claims (12)

Patent claims Probe head for measuring spatial contours in which that of the probe touching the measuring contour is movably connected to PUhrungelemente is, characterized in that the signal generator controlling movable part in each Direction of the x-y plane and at the same time in the perpendicular to the x-y plane z-axis is movable and thereby via slideways with according to certain requirements the predetermined course acts on electrical signal generators. 2. Probe head according to claim 1, characterized in that the movement of the moving part in the three coordinates by combining a spherical with a translational bearing is achieved. 3. Probe according to claim 1 and 2, characterized in that the Contour of the moving part, which controls the electrical signal generator, designed in this way that the greatest possible sensitivity with extensive linearity between the distance and the evaluation signal. 4. Probe head according to claim 1. t 3. characterized in that the Contour of the moving part, which controls the electrical signal generator, outside of the area used for the measurement is designed so that a maximum Free travel of the moving part results beyond the measuring range. 5. Probe according to claim 1 + 4, characterized in that the The contour of the moving part that controls the signal generator is designed as an outer contour will. 6. Probe head according to claim 1 + 4, characterized in that the The contour of the moving part that controls the signal transmitter is designed as an inner contour will. 7. Probe according to claim 1 + 6, characterized in that the The contour element of the moving part is produced as a rotationally symmetrical turned part will. 8. probe head according to claim 1 + 7, characterized in that the Movement of the movable part in the x-y plane by locking the movable part Part is prevented and movement is only possible in the z-axis. 9. Probe head according to claim 1. 8. characterized in that when used of lever switches as a signal transmitter of the contact point when deflected by the emigration errors arising from the leasing level are corrected electrically. 10. Probe according to claim 1 + 9, characterized in that from the signals of the encoder controlled by the moving part in defined positions of the moving part impulses are derived. 11. Probe according to claim io. characterized in that from the A pulse is then derived from the signals from the transmitter when the central axis of the button is on which bezishon the measuring coordinates of the machine, the contour to be measured intersects or touched. 12. Probe head according to claim 10, characterized in that from the Signalän the encoder then a pulse is derived when the measuring range of the probe is exceeded.